<HTML>
<BODY BGCOLOR="white">
<PRE>
<FONT color="green">001</FONT>    /*<a name="line.1"></a>
<FONT color="green">002</FONT>     * Licensed to the Apache Software Foundation (ASF) under one or more<a name="line.2"></a>
<FONT color="green">003</FONT>     * contributor license agreements.  See the NOTICE file distributed with<a name="line.3"></a>
<FONT color="green">004</FONT>     * this work for additional information regarding copyright ownership.<a name="line.4"></a>
<FONT color="green">005</FONT>     * The ASF licenses this file to You under the Apache License, Version 2.0<a name="line.5"></a>
<FONT color="green">006</FONT>     * (the "License"); you may not use this file except in compliance with<a name="line.6"></a>
<FONT color="green">007</FONT>     * the License.  You may obtain a copy of the License at<a name="line.7"></a>
<FONT color="green">008</FONT>     *<a name="line.8"></a>
<FONT color="green">009</FONT>     *      http://www.apache.org/licenses/LICENSE-2.0<a name="line.9"></a>
<FONT color="green">010</FONT>     *<a name="line.10"></a>
<FONT color="green">011</FONT>     * Unless required by applicable law or agreed to in writing, software<a name="line.11"></a>
<FONT color="green">012</FONT>     * distributed under the License is distributed on an "AS IS" BASIS,<a name="line.12"></a>
<FONT color="green">013</FONT>     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.<a name="line.13"></a>
<FONT color="green">014</FONT>     * See the License for the specific language governing permissions and<a name="line.14"></a>
<FONT color="green">015</FONT>     * limitations under the License.<a name="line.15"></a>
<FONT color="green">016</FONT>     */<a name="line.16"></a>
<FONT color="green">017</FONT>    <a name="line.17"></a>
<FONT color="green">018</FONT>    package org.apache.commons.math.optimization.fitting;<a name="line.18"></a>
<FONT color="green">019</FONT>    <a name="line.19"></a>
<FONT color="green">020</FONT>    import java.io.Serializable;<a name="line.20"></a>
<FONT color="green">021</FONT>    <a name="line.21"></a>
<FONT color="green">022</FONT>    import org.apache.commons.math.analysis.UnivariateRealFunction;<a name="line.22"></a>
<FONT color="green">023</FONT>    import org.apache.commons.math.exception.DimensionMismatchException;<a name="line.23"></a>
<FONT color="green">024</FONT>    import org.apache.commons.math.exception.util.LocalizedFormats;<a name="line.24"></a>
<FONT color="green">025</FONT>    import org.apache.commons.math.exception.ZeroException;<a name="line.25"></a>
<FONT color="green">026</FONT>    import org.apache.commons.math.exception.NullArgumentException;<a name="line.26"></a>
<FONT color="green">027</FONT>    <a name="line.27"></a>
<FONT color="green">028</FONT>    /**<a name="line.28"></a>
<FONT color="green">029</FONT>     * The derivative of {@link GaussianFunction}.  Specifically:<a name="line.29"></a>
<FONT color="green">030</FONT>     * &lt;p&gt;<a name="line.30"></a>
<FONT color="green">031</FONT>     * &lt;tt&gt;f'(x) = (-b / (d^2)) * (x - c) * exp(-((x - c)^2) / (2*(d^2)))&lt;/tt&gt;<a name="line.31"></a>
<FONT color="green">032</FONT>     * &lt;p&gt;<a name="line.32"></a>
<FONT color="green">033</FONT>     * Notation key:<a name="line.33"></a>
<FONT color="green">034</FONT>     * &lt;ul&gt;<a name="line.34"></a>
<FONT color="green">035</FONT>     * &lt;li&gt;&lt;tt&gt;x^n&lt;/tt&gt;: &lt;tt&gt;x&lt;/tt&gt; raised to the power of &lt;tt&gt;n&lt;/tt&gt;<a name="line.35"></a>
<FONT color="green">036</FONT>     * &lt;li&gt;&lt;tt&gt;exp(x)&lt;/tt&gt;: &lt;i&gt;e&lt;/i&gt;&lt;tt&gt;^x&lt;/tt&gt;<a name="line.36"></a>
<FONT color="green">037</FONT>     * &lt;/ul&gt;<a name="line.37"></a>
<FONT color="green">038</FONT>     *<a name="line.38"></a>
<FONT color="green">039</FONT>     * @since 2.2<a name="line.39"></a>
<FONT color="green">040</FONT>     * @version $Revision: 1037327 $ $Date: 2010-11-20 21:57:37 +0100 (sam. 20 nov. 2010) $<a name="line.40"></a>
<FONT color="green">041</FONT>     */<a name="line.41"></a>
<FONT color="green">042</FONT>    public class GaussianDerivativeFunction implements UnivariateRealFunction, Serializable {<a name="line.42"></a>
<FONT color="green">043</FONT>    <a name="line.43"></a>
<FONT color="green">044</FONT>        /** Serializable version identifier. */<a name="line.44"></a>
<FONT color="green">045</FONT>        private static final long serialVersionUID = -6500229089670174766L;<a name="line.45"></a>
<FONT color="green">046</FONT>    <a name="line.46"></a>
<FONT color="green">047</FONT>        /** Parameter b of this function. */<a name="line.47"></a>
<FONT color="green">048</FONT>        private final double b;<a name="line.48"></a>
<FONT color="green">049</FONT>    <a name="line.49"></a>
<FONT color="green">050</FONT>        /** Parameter c of this function. */<a name="line.50"></a>
<FONT color="green">051</FONT>        private final double c;<a name="line.51"></a>
<FONT color="green">052</FONT>    <a name="line.52"></a>
<FONT color="green">053</FONT>        /** Square of the parameter d of this function. */<a name="line.53"></a>
<FONT color="green">054</FONT>        private final double d2;<a name="line.54"></a>
<FONT color="green">055</FONT>    <a name="line.55"></a>
<FONT color="green">056</FONT>        /**<a name="line.56"></a>
<FONT color="green">057</FONT>         * Constructs an instance with the specified parameters.<a name="line.57"></a>
<FONT color="green">058</FONT>         *<a name="line.58"></a>
<FONT color="green">059</FONT>         * @param b &lt;tt&gt;b&lt;/tt&gt; parameter value<a name="line.59"></a>
<FONT color="green">060</FONT>         * @param c &lt;tt&gt;c&lt;/tt&gt; parameter value<a name="line.60"></a>
<FONT color="green">061</FONT>         * @param d &lt;tt&gt;d&lt;/tt&gt; parameter value<a name="line.61"></a>
<FONT color="green">062</FONT>         *<a name="line.62"></a>
<FONT color="green">063</FONT>         * @throws IllegalArgumentException if &lt;code&gt;d&lt;/code&gt; is 0<a name="line.63"></a>
<FONT color="green">064</FONT>         */<a name="line.64"></a>
<FONT color="green">065</FONT>        public GaussianDerivativeFunction(double b, double c, double d) {<a name="line.65"></a>
<FONT color="green">066</FONT>            if (d == 0.0) {<a name="line.66"></a>
<FONT color="green">067</FONT>                throw new ZeroException();<a name="line.67"></a>
<FONT color="green">068</FONT>            }<a name="line.68"></a>
<FONT color="green">069</FONT>            this.b = b;<a name="line.69"></a>
<FONT color="green">070</FONT>            this.c = c;<a name="line.70"></a>
<FONT color="green">071</FONT>            this.d2 = d * d;<a name="line.71"></a>
<FONT color="green">072</FONT>        }<a name="line.72"></a>
<FONT color="green">073</FONT>    <a name="line.73"></a>
<FONT color="green">074</FONT>        /**<a name="line.74"></a>
<FONT color="green">075</FONT>         * Constructs an instance with the specified parameters.<a name="line.75"></a>
<FONT color="green">076</FONT>         *<a name="line.76"></a>
<FONT color="green">077</FONT>         * @param parameters &lt;tt&gt;b&lt;/tt&gt;, &lt;tt&gt;c&lt;/tt&gt;, and &lt;tt&gt;d&lt;/tt&gt; parameter values<a name="line.77"></a>
<FONT color="green">078</FONT>         *<a name="line.78"></a>
<FONT color="green">079</FONT>         * @throws IllegalArgumentException if &lt;code&gt;parameters&lt;/code&gt; is null,<a name="line.79"></a>
<FONT color="green">080</FONT>         *         &lt;code&gt;parameters&lt;/code&gt; length is not 3, or if<a name="line.80"></a>
<FONT color="green">081</FONT>         *         &lt;code&gt;parameters[2]&lt;/code&gt; is 0<a name="line.81"></a>
<FONT color="green">082</FONT>         */<a name="line.82"></a>
<FONT color="green">083</FONT>        public GaussianDerivativeFunction(double[] parameters) {<a name="line.83"></a>
<FONT color="green">084</FONT>            if (parameters == null) {<a name="line.84"></a>
<FONT color="green">085</FONT>                throw new NullArgumentException(LocalizedFormats.INPUT_ARRAY);<a name="line.85"></a>
<FONT color="green">086</FONT>            }<a name="line.86"></a>
<FONT color="green">087</FONT>            if (parameters.length != 3) {<a name="line.87"></a>
<FONT color="green">088</FONT>                throw new DimensionMismatchException(3, parameters.length);<a name="line.88"></a>
<FONT color="green">089</FONT>            }<a name="line.89"></a>
<FONT color="green">090</FONT>            if (parameters[2] == 0.0) {<a name="line.90"></a>
<FONT color="green">091</FONT>                throw new ZeroException();<a name="line.91"></a>
<FONT color="green">092</FONT>            }<a name="line.92"></a>
<FONT color="green">093</FONT>            this.b = parameters[0];<a name="line.93"></a>
<FONT color="green">094</FONT>            this.c = parameters[1];<a name="line.94"></a>
<FONT color="green">095</FONT>            this.d2 = parameters[2] * parameters[2];<a name="line.95"></a>
<FONT color="green">096</FONT>        }<a name="line.96"></a>
<FONT color="green">097</FONT>    <a name="line.97"></a>
<FONT color="green">098</FONT>        /** {@inheritDoc} */<a name="line.98"></a>
<FONT color="green">099</FONT>        public double value(double x) {<a name="line.99"></a>
<FONT color="green">100</FONT>            final double xMc = x - c;<a name="line.100"></a>
<FONT color="green">101</FONT>            return (-b / d2) * xMc * Math.exp(-(xMc * xMc) / (2.0 * d2));<a name="line.101"></a>
<FONT color="green">102</FONT>        }<a name="line.102"></a>
<FONT color="green">103</FONT>    <a name="line.103"></a>
<FONT color="green">104</FONT>    }<a name="line.104"></a>




























































</PRE>
</BODY>
</HTML>
